Oscillation generator



April 6 1926. 1,579,894

H. C. SNOOK OSCILLATION GENERATOR Filed May 31, 1922 Wren/0r: flame/-675/7004 UNITED STATES Patented Apr.

' PATENT OFFICE.

HOMER C. SNOOK, OF SOUTH ORANGE, NEW JERSEY, ASSIGNOR TO WESTERNELECTRIC COMPANY, INCORPORATED, 013 NEW YORK, N. Y., A CORPORATION OFNEW YORK.

OSOILLATION GENERATOR.

Application filed May 31, 1922. Serial- No. 564,844.

. 1'0 all whom it may concern:

Be it known that I, HOMER C. SNOOK, a citizen of the United States ofAmerica, residing at South Orange, in the county of Es sex and State ofNew Jersey, certain new and useful Improvements in OscillationGenerators, of which the following is a full, clear, concise, andexactqdescription.

This invention relates to a method of and means for producing electricoscillations by means of an electric discharge device having a dividedspace current path. V

The present invention is directed to the use of an electric dischargedevice having a heated cathode or electron emitter and an anode composedof a plurality of independent members. The electron emitter is connectedthrough a source 01 electric energy to the mid-point of a coil, oneterminal of which is connected to one-half of the said or an unbalancedcondition occur anode members and the other terminal of which isconnected to the other half of the anode members. A tuned circuit isassociated with said coil. Under normal conditions the current suppliedby the space source will divide at the mid-point of the coil and thenumber of electrons flowing from the heated cathode to each set of anodemembers will be equal. However, should a disturance in the tuned circuitassociated with the coil, an alternating E. M. F. will be impressed uponthe coil and disturb the balance whereby the positive potential of oneset of anode members will be increased and that of the other decreasedin which case a greater set-will be number of electrons will flow to oneset of anode members than to the other set. The two sets of anodemembers are arranged sufliciently close to each other that the morenegative condition of one set causes it to act as a control ordeflecting electrode, with respect to the other, set thereby magnifyingthe eflcct produced by the original disturbance. An increase in theamplitude of the oscillations set up in the tuned circuit will result,and produce an increase in the unbalanced effect in the respectivedischarge paths within the. device, until eventually oscillations of adefinite amplitude are generatcd in the tuned circuit.

One object of this invention is the provision of a simple and convenientarrangehave invented.

ment whereby sustained oscillations may be produced from a directcurrent source. Another object is to provide an arrangement in whiclrthespace potentials impressedupon a plurality of anodes within an electricdischarge device may be cyclically varied to control the supply ofenergy to a frequency determining means associated with the device,whereby sustained oscillations may be generated.

For a complete understanding of the invention and the operation of itsseveral parts, reference may be made to the following description takenin conjunction with the attached drawing in which Fig. 1 shows oneapparatus for practicing the invention and Fig. 2 illustrates a slightlydifferent form of electric discharge device which may be substituted forthat shown in Fig. 1.

Referring now to Fig. 1 there is shown an electric discharge devicecomprising an evacuated vessel 1, a cathode 2 and an anode having twoclosely positioned portions 3 and 4. A source 5 supplies heating currentto the cathode or filament 2. The cathode is connected to the anode by acircuit including the space current source 6 and a coil 7 to themid-point of which the source 6 is connected, while its terminals areconnected to the anode portions 3 and 4.

Coupled to the coil 7 is a coil 8 shunted by a con-denser 9 toconstitute a tuned circuit, the period of which may be varied byadjusting either the coil 8, condenser 9 or both. The variability ofthese elements is represented by the arrows applied to them. Coupled tothe coil 8 is a coil 10 which may be connected to a load circuit.

Normally the electrons emitted by the cathode 2 will be discharged tothe anodes 3 and 4: under the influence of the potential supplied by thesource 6 and, since the voltage impressed upon these portions is thesame, an equal number of electrons will flow to each. Any change in thevoltages impressed upon the anodes 3 and 4 with respect to each otherwill alter the potentials of their respective circuits relatively to thecathode 2 and hence a larger number of electrons will flow to one anodeportion and a lesser number to the other. This will result in a changeof current flow through the coil 7 which by virtue of the coupling be.-tween the coils 7 and 8 will be transferred field of the other towardthe cathodewhereby each of these electrodes alternately acts as acontrol or deflecting electrode with respect to the other, therebymagnifying the effect produced by a change in the voltages impressedthereon.

In passing it may be noted that the E. M.

F. produced in the tuned circuit 8--9 by reaction from the coil 7 may beexpressed as dI 6=ka where k is a function of a number of factorsincluding the voltage of the battery 6, the geometry of theintra-electrode space, the number of turns in the coil 7, thetemperature of the filament 2, the mutual inductance between the coils 7and 8 and the character of the filament 2.

Referring to Fig. 2 there is shown an electric discharge devicecomprising an evacuated vessel 11, an electron emitter or cathode 12 anda subdivided anode consisting of a plurality of alternate sections 13and 14. This device may be substituted for that shown in Fig. 1, thesource 5 being connected to the leads 15 and the coil 7 to the leads 16.This design of discharge device is more sensitive than that describedwith reference to Fig. 1 due to the more intimate association of thesections of the anode. As described above the E. M. F. produced in thetuned circuit 89 by reaction from the coil 7 is dependent upon, amongother things, the factor k.

which in turn is a function of the geometry of the intra-electrodespace. By employing the anode construction shown in Fig. 2 the factor kis increased, and hence a smaller potential change will produce the samecurrent change in a given length of time than is possible with thedevice of Fig. 1.

While in the drawing the anodes are shown as flat plates it will beapparent that they may be cylinders surrounding the oathode or aplurality of fiat or curvilinear sections one on each side of thecathode and electrically connectedtogether to constitute a singleelectrode.

In the preceding description one arrangement for practicing thepresent-invention has been set forth completely and clearly to disclosethe principles involved in its operation. Obviously, this invention isnot limited to the arrangement and specfic details described, but onlyby the scope of the attached claims.

What is claimed is:

1. An oscillation generator comprising a pure electron discharge devicehaving a cathode, a plurality of anodes, means for establishing anelectron stream from said cathode to each anode and means coupled tosaid anodes for varying the potentials impressed thereon, said anodesbeing so arranged with respect to each other that the one having themore negative potential acts asha control electrode with respect to theot er.

2. An oscillation generator comprising a pure electron discharge devicehaving a cathode, a plural part anode, .means for impressing adifference in potential between said cathode and anode to establishelectron streams between said cathode and said anode parts and means forvarying the potentials applied to said anode parts, said anode partsbeing so closely arranged that the field of each modifies the resultantelectric field of the other toward the cathode.

3. An oscillation generator comprising a pure electron discharge devicehaving a cathode, a plurality of anodes, a coil having its terminalsconnected to different anodes, a source of space current connected tothe mid-point of said coil and to said cathode, and a frequencydetermining means coupled to said coil to supply an alternatingpotential to said anodes, said anodes beingso arranged with respect toeach other that each alternately acts as a control electrode withrespect to the other.

4. A method of generating electrical oscillations by means of anarrangement including a pure electron discharge device having a cathodeand a pluraligy of closely arranged anodes, said metho comprisingestablishing electron streams from said cathode D said anodes,alternately varying the pote .tials of said anodes in response to anoscillating current and utilizing the electric field of eachanode tomodify the resultant field of the other toward the cathode.

In witness whereof, I hereunto subscribe my name this 29th day of May A.D., 1922.

